Dental handpiece construction



Nov. 6, 1962 J. v. BORDEN 3,061,930

DENTAL HANDPIECE CONSTRUCTION Filed July 28, 1959 INVENTOR JOHN L/ BORDEN ATTORNEYS United States Patent Oflice 3,%1,3li Patented Nov. 6, 1962 3,061,934) DENTAL PIECE CONSTRUCTION John V. Borden, Ranson, W. Va. Filed July 28, 1959, Ser. No. 830,101 9 Ciaims. (Cl. 32-27) This invention relates generally to the construction of a dental handpiece, and particularly to a construction of a handpiece of the fluid turbine, high-speed type, which requires cooling and lubricating means in the vicinity of the driven bur.

High speed drills developed in recent years have become quite complex and sophisticated with each additional improvement. This complexity, coupled with the high intensity of the vibrations transmitted from the rotating elements, has caused looseness and damage to various connecting points of the handpiece. The fluids for cooling, and the fluids for driving the turbine, are most conveniently delivered to this point of use interiorly of the dental handpiece handle. This adds to the already existing complexities and production difliculties. It is therefore an objective of this invention to provide an improved neck portion construction for a dental handpiece.

It is a further objective of the invention to provide for a handpiece, a substantially solid neck portion upon which various conventional machine operations have been performed, such that the neck portion may achieve its connection purposes and all or any of the fluid delivery missions assigned to it.

Further objectives and advantages of this invention will be apparent from the following description and claims wherein the construction, arrangement and cooperation of the several parts of the instrument are set forth.

In the drawings:

FIG. 1 is a cross-sectional view of a dental handpiece having portions of the interior of the handpiece in elevation;

FIG. 2 is a perspective view of a portion of the neck portion of the handpiece shown in FIG. 1;

FIG. 3 is an end view of the neck portion before'attachment to the turbine housing;

, FIG. 4 is a view along the line 33 in FIG. 1;

' FIG. 5 is a view along the line 44 in FIG. 1; and

FIG. 6 is a perspective view of a different neck portion showing the variety of missions the structure of this invention may accomplish.

, Referring now to the drawings in which like numerals indicate like parts, the numeral 10 designates one form of the handpiece of this invention. The handpiece is comprised, generally, of a turbine housing 12, a neck portion 14, sleeve 16, and a hollow handle 18.

This invention relates primarily to the novel manner in which the neck portion and sleeve connect the turbine housing to the handle.

The cylindrical housing 12 encloses an air turbine assembly 24 rotatably mounted by ball bearings 26 and 28. The bur-receiving end of the housing has means therein to produce an air and Water spray and direct it to the vicinity of the bur head. The specific means for accomplishing this spray is not included as a part of this invention, but may, for instance, be of the type covered by my co-pending application Serial No. 813,092.

The particular air turbine assembly disclosed by FIG. 1 is of the type which receives a jet of air near the midsection of its rotor blades and exhausts the air at its upper and lower ends. Portions of this air are exhausted through the bearings and the remainder through the end of the handpiece. For these purposes the housing 12 has an air inlet opening 3-2, and two exhaust openings 34 and 36 formed therein.

In the past there has been some diihculty encountered in aligning and securely fastening the handle to the housing so that the proper delivery and exhaust ports in the handle would match the proper fluid delivery conduits in the handle. This fastening point is right at the point where the housing vibrations are transmitted to the handle and the resulting connection must be strong. This invention provides a neck portion 14 formed of a solid piece of material upon which various operations have been performed. The neck portion comprises a reduced portion 38 formed at one end thereof and upper and lower flats 40 and 42 which have been milled on the reduced portion. Rearwardly spaced from lower flat 42 is a transverse slot 44. Centrally drilled in neck portion 14 is the air inlet passage 46 which has a reduced portion 47 adapted to be in communication with orifice 32 of the housing 12. An air exhaust channel 48 is drilled between flats 40 and 42 offset from passage 46. Extending rearwardly from said exhaust channel is an air exhaust artery 50 which extends rearwardly through said neck portion to connect with a hose 52, or into the interior of the handle and is subsequently exhausted through the end of the handpiece.

Also drilled in the'neck portion, and in communication with the transverse slot 44, is the water inlet passage 54 which extends rearwardly through the neck portion and is connected to water pipe 56. Extending into slot 44 from the other direction is water direction tube 58 which directs water to a point 60 where the air and water form a spray. In FIG. 1 it can be seen that tube 58 extends well within chamber 44 an amount 59. This extension operates somewhat as a screening means which aids in preventing foreign materials in the water from entering tube 58. These milling operations are conveniently accomplished while the neck 14 is longitudinally straight. The neck piece is then bent into the contra-angle shape if desired.

After the relatively simplemechanical operations of lathing reduced section 38, milling recesses 40 and 42, and slot 44, and drilling air exhaust channel 48, a cylindrical sleeve 16 is snugly fitted over these surface configurations and the required chambers are formed. It is a simple matter to then align the correct chambers with the proper orifices in housing 12. There is an open:- ing 62 in the sleeve 16 so that water directing tube 58 may enter the chamber formed by slot 44.

The neck portion is soldered or otherwise connected to the housing 12. It can be seen that the structureshown presents a relatively solid member at the point of at tachment between the housing and neck piece. There are no normally weak tubular andconduit connections which are likely to shake loose when the structure of this invention is used.

Theinvention is not limited to the type grooves and chambers shown and described. For instance, FIG; 6 shows a neck portion 70 having dual air supply apertures 72 and 74 in the event the particular turbine used might be of the twin turbine type. The portion 70 also shows a side chamber 76 in the event a side exhaust is to be used. This demonstrates how the neck portion is adaptable to be used with handpieces requiring a variety of functions to be performed. If, for instance, there was not to be any water cooling with a particular handpiece, the water delivery slots and apertures would not have to be machined in the neck piece.

In a general manner, while I have, in the above description, disclosed what I deem to be practical and eflicient embodiments of my invention, it should be well understood that I do not wish to be limited thereto, as there might be changes made in the arrangement, disposition and form of the parts without departing from within the scope of the accompanying claims.

I claim:

1. A high-speed dental drill of the type which comprises a handpiece having a turbine housing at one end and having connecting means at the other end for power fluid for the turbine and coolant fluid which forms a cooling spray at the drilling area comprising, in combination, a housing for an air-driven turbine, said housing having a first opening therein to receive air under pressure, and a second opening for exhausting air from said housing, a handle separably connected to said housmg, said handle being substantially solid and having a portion of reduced diameter near said housing, said por-. tion having a hole therein and a flat section along its outside diameter, a sleeve connected between said housing and said handle and fitted over said reduced portion forming a chamber at said flat section, said chamher being in communication with said exhaust port and said hole being in communication with said first opening.

2. The dental drill described in claim 1 wherein there are means associated with said flat section in communication with the atmosphere.

3. A high-speed dental drill of the type which comprises a handpiece having a turbine housing at one end and having connecting means at the other end for power fluid for the turbine and coolant fluid which'forms a cooling spray at the drilling area comprising, in combination, a housing for an air-driven turbine, said housing having a first opening therein to receive air under pressure, and second openings for exhausting air from said housing, a handle separably connected to said housing, said handle being substantially solid and having 'a portion of reduced diameter near said housing, said portion having a hole running longitudinally therethrough and a plurality of flat sections along its outside diameter, a sleeve connected between said housing and said handle and fitted over said reduced portion forming chambers with said flat sections, said chambers being in communication with said exhaust ports and said hole being in communication with said first opening and a source of pressurized air.

4. A high-speed fluid-driven drill of the type which comprises a handpiece having a turbine housing at one end and having connecting means at the other end for power fluid for the turbine comprising a housing for a fluid-driven turbine, said housing having a first opening therein to receive air under pressure, and a second opening for exhausting air from said housing, a handle separably connected to said housing, said handle being substantially solid and having a portion of reduced diameter near said housing, said portion having a hole therein and a flat section along its outside diameter, a sleeve connected between said housing and said handle and fitted over said reduced portion forming a chamber with said flat section, said chamber being in communication with said exhaust port and said hole being in communication with said first opening.

5. A high-speed dental drill of the type which comprises a handpiece having a turbine housing at one end and having connecting means at the other end for power fluid for the turbine and coolant fluid which forms a cooling spray at the drilling area comprising, in combination, a housing for an air-driven turbine, said housing having a first opening therein to receive air under pressure, and a second opening for exhausting air from said housing, a handle separably connected to said housing, said handle being substantially solid and having a portion of reduced diameter near said housing, said portion having a hole therein, a flat section along its outside surface, and a transverse slot along another portion of its surface, a sleeve connected between said housing and said handle and fitted over said reduced portion forming a first chamber at said flat section and a second chamber at said slot, said first chamber being in communication with said exhaust port, said hole being in communication with said first opening, and said slot eenoao being in communication with means to deliver said coolant fluid to the area to be drilled. a

-6. A fluid-driven high-speed dental drill comprising, in combination, a housing for the rotating elements, a handle connected to said housing, said handle comprised of a substantially solid portion and a substantially hollow portion, means in said hollow portion for delivering coolant and the power fluid to said solid portion, said solid portion having an end of reduced diameter connected to said housing, said end having a plurality of flat sections, and a groove machined 0n its'outer surface, a sleeve fitted over said end to form first chambers of said flat sections and a second chamber of said groove, said first chambers receiving the coolant from said hollow portion, and said second chamber receiving exhaust air from said dental drill.

7. In a fluid-driven dental drill of the type which comprises a handpiece having a turbine housing at one end and having connecting means at the other end for power fluid for the turbine composed of two separable sub-assemblies, one of said sub-assemblies including a housing for a turbine rotor, the other of said sub-assemblies including a handle, each of said sub-assemblies being provided with two conduit means forming portions of a closed circuit to supply pressurized fluid to the rotor and to exhaust spent fluid therefrom, one of said sub-assemblies being provided with a tubular sleeve portion, the other of said sub-assemblies being provided with a projecting portion separably fitted within said sleeve portion, said projecting portion being provided with a flat section forming a chamber with said sleeve portion, one of the conduit means of each sub-assembly terminating in a mating aperture provided in each of said sub-assemblies in communication with each other, the other conduit means of each sub-assembly terminating in communication with the chamber formed by the sleeve and the flat section.

8. In a fluid-driven dental drill of the type which comprises a handpiece having a turbine housing and a coolant fluid discharge orifice adjacent said housing at one end and having connecting means at the other end for power fluid composed of two separable sub-assemblies, one of said sub-assemblies including a housing for a turbine rotor, the other of said sub-assemblies including a handle, each of said sub-assemblies being provided with three conduit means, each conduit means of one sub-assembly being in separate communication with a conduit means of the other sub-assembly, one of said sub-assemblies being provided with a tubular sleeve portion, the other of said sub-assemblies being provided with a projecting portion fitted within said sleeve portion, said projecting portion being provided with a pair of flat sections forming a pair of chambers with said sleeve, one of the conduit means of each sub-assembly terminating in a mating aperture provided in each of said sub-assemblies in separable communication with each other, each of the remaining conduit means of each sub-assembly terminating in communication respectively with one of the chambers formed by the sleeve and the pair of flat sections.

9. The invention as defined in claim 8, wherein said flat sections are longitudinally offset with respect to the axis of said sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 

